Attack Surface: Network Exposure and Unauthorized Access
Description: Direct, unauthorized access to the Dragonfly instance over the network.
Dragonfly Contribution: Dragonfly listens on a TCP port (default 6379) for client connections. Its in-memory nature makes unauthorized access particularly damaging.
Example: An attacker scans for open port 6379 on the public internet and finds a Dragonfly instance with no authentication enabled. They connect and issue FLUSHALL to delete all data.
Impact: Complete data loss, data breach, service disruption.
Risk Severity: Critical
Mitigation Strategies:
* Firewall Rules: Implement strict firewall rules (using iptables, ufw, cloud provider security groups, etc.) to allow connections only from trusted IP addresses/ranges (application servers, specific development machines). Block all other inbound traffic to the Dragonfly port.
* Network Segmentation: Place Dragonfly on a private network or within a secure VPC (Virtual Private Cloud) that is not directly accessible from the public internet. Use network isolation techniques (e.g., subnets, security groups) to limit communication between Dragonfly and other services.
* Bind to Specific Interface: Configure Dragonfly to bind to a specific, internal network interface (e.g., 127.0.0.1 for local-only access, or a private network IP). Avoid binding to 0.0.0.0 unless absolutely necessary and properly firewalled.
* VPN/Private Network: Use a VPN or private network connection (e.g., VPC peering) to securely connect to the Dragonfly instance.
* Authentication: Always enable authentication using the requirepass configuration option. Use a strong, randomly generated, and regularly rotated password. Store this password securely (e.g., using a secrets management system).
* TLS Encryption: Enable TLS encryption for all communication with Dragonfly. This requires generating and configuring certificates for both the server and clients. Ensure clients are configured to use TLS and verify the server's certificate.
Attack Surface: Data Manipulation (via Dragonfly Commands)
Description: Unauthorized modification or deletion of data stored in Dragonfly through direct command execution. This differs from the previous point by focusing on authorized network connections that are then misused.
Dragonfly Contribution: Dragonfly's command-based interface allows for direct manipulation of data. If an attacker gains access (even with limited privileges), they can issue commands.
Example: An attacker compromises an application server that has legitimate access to Dragonfly. The attacker then uses the established connection to issue commands like DEL, SET (with malicious data), or even FLUSHALL if permissions allow.
Impact: Data corruption, data loss, data breach, potential for further exploitation.
Risk Severity: High
Mitigation Strategies:
* Principle of Least Privilege (Dragonfly Level): If Dragonfly's ACL features are used (available in later versions, similar to Redis 6+), grant only the minimum necessary permissions to each connecting client/application. For example, a read-only cache should not have write access.
* Command Monitoring: Monitor executed commands for suspicious patterns. This requires more advanced logging and analysis.
* Input Validation (Application Side): While this isn't directly Dragonfly, rigorous input validation on the application side is crucial to prevent malicious commands from ever reaching Dragonfly. This is the primary defense.
* Separate Instances: Consider using separate Dragonfly instances for different data sets or trust levels, limiting the blast radius of a compromise.
Attack Surface: Denial of Service (DoS) - Resource Exhaustion
Description: Attacks that aim to make Dragonfly unavailable by exhausting its resources (primarily memory).
Dragonfly Contribution: Dragonfly's in-memory nature makes it inherently vulnerable to memory exhaustion.
Example: An attacker sends a flood of SET commands with very large values, consuming all available memory and causing Dragonfly to crash or become unresponsive.
Impact: Service disruption, potential data loss (if persistence is not configured or is overwhelmed).
Risk Severity: High
Mitigation Strategies:
* Memory Limits (maxmemory): Crucially, configure the maxmemory option in Dragonfly to set a hard limit on the amount of memory it can use. This is the primary defense against memory exhaustion DoS.
* Eviction Policy: Choose an appropriate eviction policy (e.g., volatile-lru, allkeys-lru, volatile-ttl) to control how data is evicted when the maxmemory limit is reached. The choice of policy depends on the application's needs.
* Resource Monitoring: Continuously monitor Dragonfly's memory usage, CPU usage, and number of connections to detect potential DoS attacks early.
* Lua Scripting Limits: If using Lua scripting, carefully review and test scripts for potential resource exhaustion. Set resource limits for Lua scripts if supported by your Dragonfly version and client library.